This invention relates to the guidance of flying bodies and, more particularly, to a novel method of and apparatus for the thrust vector control of such flying bodies by means of a single jet rudder which, to produce a guiding force for the flying body, is dipped into and deflects the single jet driving the flying body.
The actuation of such a jet rudder is responsive to guide signals transmitted to the flying body. These guide signals are formed as horizontal and vertical guide signals K.sub.y and K.sub.z of a cartesian coordinate system which is referred to the flying body and to an associated guide device. Prior to their transmission to the flying body, for example in the form of signal potentials, these horizontal and vertical guide signals are converted into polar guide signals .theta. and .alpha. by coordinate conversion and by the vector summation illustrated graphically in FIG. 1.
With respect to the control of a flying body by means of a single jet rudder, as in the present case, the entry and exit angles .phi..sub.1 and .phi..sub.2 (FIG. 2) for the jet rudder, for a rotation through 360.degree. of the flying body, are calculated from the polar guide signals. More specifically, in each case the calculation is effected from the guide vector .theta. and the angle .alpha. as follows: EQU .phi..sub.1 = .alpha. - ( a.theta./2) EQU .phi..sub.2 = .alpha. + (a.theta./2)
In the above formulae, a is a constant factor.
In this manner, the constant relationship of the reference planes of the guide arrangement and of the rotating flying body is maintained, and a single jet rudder, for the angular ranges corresponding to the cartesian guiding signals calculated on the flying body rotating about its longitudinal axis, is dipped into the jet stream.
The constructional advantages and the increased reliability which are characteristic of thrust vector control of a rolling flying body by means of a single jet rudder have to be balanced against the great expenditure necessary for the coordinate transducer necessary for the conversion of the cartesian guide signals into polar guide signals. Alternatively, if a servo system is used, then the use of mechanical parts which are subject to wear and the lower limit of such a servo system, have to be considered. As is known to those skilled in the art, the guiding device, in contrast to the flying body proper, is not lost and does not have to be replaced after each use.
An object of the present invention is to provide a new method for controlling the thrust vector and which is free of the drawbacks of prior art methods.
Another object of the invention is to provide such a method for the control of the thrust vector in which simultaneously obtained vertical and horizontal guide signals are transmitted to the flying body in the form of timed control pulse sequences in each of which each pulse is phase rigid with respect to a respective angular position of rotation of the flying body.
A further object of the invention is to provide a new method for the control of the thrust vector, such as just mentioned, in which, by comparing the vertical and horizontal signal potentials with function-potentials, each of which is phase rigid with respect to a respective angular position of rotation of the flying body, control signals are produced in the manner of a pulse width modulation.
Yet another object of the invention is to provide such a method for the control of the thrust vector wherein the pulse widths of the guide pulses, in each instance, are proportional to the respective signal potentials.
A further object of the invention is to provide a method for the control of the thrust vector and based on the consideration that the simultaneously obtained horizontal and vertical guide signals, which normally are simultaneously required for guiding the course of a flying body having a single jet rudder, are obtained in the form of timed control pulse sequences in each of which each pulse is effective in a respective angular position of rotation of the rotating flying body.
Due to the rotational inertia of the flying body, the transverse forces, which are caused by the guide signals given successively in different angular ranges, are so integrated that these cause the same change in the course of the flying body as would be caused by the guide signals K.sub.y and K.sub.z.
In this manner, the stable signal sector positions, as illustrated in FIG. 3, are obtained. In these stable signal sector positions, only the sector widths, corresponding to the magnitude of the respectively given guide signals, may continuously change. With respect to a constant sector position, the following relation obtains:
Guide signal "left" .beta. = 90.degree.
Guide signal "high" .gamma. = 180.degree.
Guide signal "right" .delta. = 270.degree.
The associated exit and entry angles of the jet rudder, with a variable sector width, then are: EQU .phi..sub.2 - .phi..sub.1 , .phi..sub.4 - .phi..sub.3 , or .phi..sub.6 - .phi..sub.5
In the foregoing: EQU .phi..sub.2 - .phi..sub.1 = ak.sub.y for K.sub.y &lt; 0 EQU .phi..sub.4 - .phi..sub.3 = aK.sub.z for K.sub.z .gtoreq. 0 EQU .phi..sub.6 - .phi..sub.5 = aK.sub.y for K.sub.y &gt; 0
This means that coordinate transducers or servosystems are no longer required. Furthermore, due to the gravitational pull acting on the flying body, it is unnecessary to use a further sector position for "low" signals so that the sector position .epsilon. = 360.degree. is vacant and thus may be used for other signals or for return information from the flying body to the guide device and to the guide station. Additionally, the association of the obtained cartesian guide signals with the respective angular positions of rotation of the flying body may now be effected by logic circuits, so that a simple electronic construction and design of the guiding arrangement is possible.
In accordance with a further object of the invention, two function potentials are produced which are phase rigid relative to the angular position of rotation of the flying body. These function potentials are produced both in the horizontal and also in the vertical signal directions.
According to a preferred embodiment of the invention, however, only a single function potential is produced in the vertical signal direction, and is phase rigid to the angular position of rotation of the flying body. Thereby, the guide pulses derived therefrom are directed in their action direction in opposition to the earth's gravity.
A further object of the invention is to provide a thrust vector control method, as mentioned, in which, in order to increase the response sensitivity and to compensate for dead periods of the jet rudder system, the signal potential in the horizontal signal direction, in the vertical signal direction, or in both signal directions, is superposed by a bias potential or "pre-potential" which preferably is variable.
Another object of the invention is to provide a control apparatus for performing the control method of the invention.
A further object of the invention is to provide such a control apparatus including at least three function generators, controlled by a synchronizing unit, for producing function potentials which are phase rigid relative to respective angular positions of rotation of the flying body.
Still another object of the invention is to provide such a control apparatus, comprising comparators connected to the outputs of the function generators and which are also connected with a guide device for producing the cartesian guide signals as well as with an addition stage connected to the outputs of the comparators. From this addition stage, there can be taken output pulse signals comprising the guide signals.